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<div class="titlepage"><div><div><h3 class="title">
<a name="boost_asio.reference.deferred_t"></a><a class="link" href="deferred_t.html" title="deferred_t">deferred_t</a>
</h3></div></div></div>
<p>
        <a class="indexterm" name="boost_asio.indexterm.deferred_t"></a>
      </p>
<p>
        Class used to specify that an asynchronous operation should return a function
        object to lazily launch the operation.
      </p>
<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">deferred_t</span>
</pre>
<h5>
<a name="boost_asio.reference.deferred_t.h0"></a>
        <span class="phrase"><a name="boost_asio.reference.deferred_t.types"></a></span><a class="link" href="deferred_t.html#boost_asio.reference.deferred_t.types">Types</a>
      </h5>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  Name
                </p>
              </th>
<th>
                <p>
                  Description
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <a class="link" href="deferred_t/as_default_on_t.html" title="deferred_t::as_default_on_t"><span class="bold"><strong>as_default_on_t</strong></span></a>
                </p>
              </td>
<td>
                <p>
                  Type alias to adapt an I/O object to use deferred_t as its default
                  completion token type.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="deferred_t__executor_with_default.html" title="deferred_t::executor_with_default"><span class="bold"><strong>executor_with_default</strong></span></a>
                </p>
              </td>
<td>
                <p>
                  Adapts an executor to add the deferred_t completion token as the
                  default.
                </p>
              </td>
</tr>
</tbody>
</table></div>
<h5>
<a name="boost_asio.reference.deferred_t.h1"></a>
        <span class="phrase"><a name="boost_asio.reference.deferred_t.member_functions"></a></span><a class="link" href="deferred_t.html#boost_asio.reference.deferred_t.member_functions">Member
        Functions</a>
      </h5>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  Name
                </p>
              </th>
<th>
                <p>
                  Description
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <a class="link" href="deferred_t/as_default_on.html" title="deferred_t::as_default_on"><span class="bold"><strong>as_default_on</strong></span></a> <span class="silver">[static]</span>
                </p>
              </td>
<td>
                <p>
                  Function helper to adapt an I/O object to use deferred_t as its
                  default completion token type.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="deferred_t/deferred_t.html" title="deferred_t::deferred_t"><span class="bold"><strong>deferred_t</strong></span></a> <span class="silver">[constructor]</span>
                </p>
              </td>
<td>
                <p>
                  Default constructor.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="deferred_t/operator_lp__rp_.html" title="deferred_t::operator()"><span class="bold"><strong>operator()</strong></span></a>
                </p>
              </td>
<td>
                <p>
                  Creates a new deferred from a function. <br> <span class="silver"> —</span><br> Passes through
                  anything that is already deferred.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="deferred_t/values.html" title="deferred_t::values"><span class="bold"><strong>values</strong></span></a> <span class="silver">[static]</span>
                </p>
              </td>
<td>
                <p>
                  Returns a deferred operation that returns the provided values.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <a class="link" href="deferred_t/when.html" title="deferred_t::when"><span class="bold"><strong>when</strong></span></a> <span class="silver">[static]</span>
                </p>
              </td>
<td>
                <p>
                  Creates a conditional object for branching deferred operations.
                </p>
              </td>
</tr>
</tbody>
</table></div>
<p>
        The <a class="link" href="deferred_t.html" title="deferred_t"><code class="computeroutput"><span class="identifier">deferred_t</span></code></a>
        class is used to indicate that an asynchronous operation should return a
        function object which is itself an initiation function. A <a class="link" href="deferred_t.html" title="deferred_t"><code class="computeroutput"><span class="identifier">deferred_t</span></code></a> object may be passed
        as a completion token to an asynchronous operation, typically as the default
        completion token:
      </p>
<pre class="programlisting"><span class="keyword">auto</span> <span class="identifier">my_deferred_op</span> <span class="special">=</span> <span class="identifier">my_socket</span><span class="special">.</span><span class="identifier">async_read_some</span><span class="special">(</span><span class="identifier">my_buffer</span><span class="special">);</span>
</pre>
<p>
        or by explicitly passing the special value <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">deferred</span></code>:
      </p>
<pre class="programlisting"><span class="keyword">auto</span> <span class="identifier">my_deferred_op</span>
 <span class="special">=</span> <span class="identifier">my_socket</span><span class="special">.</span><span class="identifier">async_read_some</span><span class="special">(</span><span class="identifier">my_buffer</span><span class="special">,</span>
     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">deferred</span><span class="special">);</span>
</pre>
<p>
        The initiating function (async_read_some in the above example) returns a
        function object that will lazily initiate the operation.
      </p>
<h5>
<a name="boost_asio.reference.deferred_t.h2"></a>
        <span class="phrase"><a name="boost_asio.reference.deferred_t.requirements"></a></span><a class="link" href="deferred_t.html#boost_asio.reference.deferred_t.requirements">Requirements</a>
      </h5>
<p>
        <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/deferred.hpp</code>
      </p>
<p>
        <span class="emphasis"><em>Convenience header: </em></span><code class="literal">boost/asio.hpp</code>
      </p>
</div>
<div class="copyright-footer">Copyright © 2003-2025 Christopher M.
      Kohlhoff<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
</div>
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